Servo power application to dies of die-casting machines



July 3, 1945. L.. H. MORIN 2,379,738

SERVO-POWER APPLICATION TO DIES OF DIE `GS'IING MCHINES Filed Aug. 14.1942 filme Patented July 3, 1945 ,y

`sitltvo Pownn OFFICE 1 DIEfCASTING MAC E'Morin, Bronx, N. Y., miglior'of onchalt toDavis Marinsky, Bronx, N. Y.

Applicativi; august 14, 1942, rsemi No. 454310` (c1. zzz-.ssl

Y )1s claims. This invention relates to die casting machines and to. theoperation of dies of machines `of this type and kind. More particularly.the

invention comprises the application of servopower to thevdies,preparatory to the pressure injection of casting material into thedies`to insure firm engagement of the dies and to resist the pressure of thecasting material injected into the die; and st ill more particularly tothe hydraulic closing of dies of high speed die casting machines. Thenovel features of the invention will be best understood from thefollowing de scription when taken together with the accompanyingdrawing, in whichcertain embodiments of the invention are disclosed, andin which the separate parts are designated by suitable referencecharacters in each of the views; and in which:

Fig. lisa diagrammatic sectional view through I the dies of a castingmachine showing the same in closed position. V p l Fig. 2 is a viewsimilar to Fig. 1 showingthe dies in open position; and

Fig. 3 is a view `similar-.to Fig. dies improperly closed. e

In the die casting art, it has been known to provide machines employinghydraulic or pneumaticY pressures for closing the dies. However, thishas been accomplished by what may "be termed a direct stroke whichinvolves rather complicated mechanism and a material waste oi power, inthat, the entire operation ot the dies has been `throughthe' mediumemployed. Furthermore such methods of operation are not practicallyapplicable to what might be termed high speed die casting machines.

` It is the purpose of my invention to provide a servo-power"application to the dies, momentarily at the point of the cycle when thedies are to be held iirmly closed, that is to say, when the castingmaterial is pressure injected into these dies. In other words, thisapplication oi power or pressure in closing the dies is employed inconjunction with and as part of the other me-v chanical means for movingthe dies toward and from each other. Furthermore, safety means areemployed to preventinjury or'dstruction to the dies and other workingparts of the machine, and also to eliminate `accidents which mightoccui,l by pressure injection of casting material into improperly closeddies, bythe squirting oi' this material beyond the limits of thedies'orthe die U1 showing the the` machine is provided, particularlyfrom the standpoint oi die operation. Y

From the standpoint of mechanical operation l f the dies, lhereindiagrammatically illustrated and described in brief, reference can bemade to the morespecic disclosure ofthe `entire opferatl'lg structure inU. vSi. patents, 1,975,966

`dated October 9, 1934, and 2,193,832 dated March e 19, 1940, in whichpatents are illustrated types of casting machines to which the presentinvention is applicable. y It will be understood, however, that thedisclosure of the invention in this respect is only illustrative of one`adaptation and use of my invention.

In the accompanying diagrammatic illustrat' tion, the mechanismcontrollingldie operation is applied to only one oi' the dies, the otherdie being shown only in part, but it will be apparent that the samestructure will -be used in .conjunction'with both dies. particularly incasting machines where both dies are movable relatively toeach other andaway from a core which supports the nished casting and which is used` toeject the casting from the impression or cavity of bothdie parts.

In the drawing, I0 represents each die part.

'I'hese die parts are moved toward and from each other by die operatingslide rods Il having angular key elements I2 fitting in correspondinggrooves I3 in the die parts so that," as the rods Il move back and forthat right angles tothe longitudinal plane of thedie parts I0, the diesare opened and closed asis specifically taught in cavity. Further, byreason of the momentaryv the patents hereinbefore cited. l

' With the fpresent structure, the die parts are each provided with longbores or passages I I, which form cylinders, into which a hydraulic orother pressure medium may be injected through pipes or tubes I5communicating with admission ports I6 which open into the cylinders I4adjacent the ends of the die parts having the vcav-- ities I1.

In` the cylinders I4 are arranged pistons or plungers I8; which extendthrough the outer ends of the die parts and have enlarged heads I9provided on outer surfaces with projecting `control fingers or dogs 2l)which form extensions on the piston, which operate in conjunction withpawls 2|. l I

Supported on the outer end of the dies are pins 22 which pass throughopenings in the enlargement I9 `of the pistons, and `springs 23 aremounted on the pins outwardly of` the enlargement and tension of thesesprings is controlled byadjustment nuts 2l arranged on the pins 22.'l'he springs 22 maintain the pistons Il in normal inwardly projectedarrangement in the cylinders I4, which inward movement is checked bystops 2i.-

The pawls 2| are rotatably supported on shafts 2t, the pawls comprisinga finger 21. notched as seen at 28, to engage the outer end of the dog2l, as seen in Fig. l of the drawing. The pawls 2| also include a finger29 adapted tooperatively engage a micro-switch 30 or the sensitiveplunger 2| of said switch for purposes later described. At 32 is shown arod pivoted to the pawl 2| for actuating said pawl in the cycle ofoperation of the machine to bring the pawl into the position shown inFig. l slightly in advance of the appli- Vcation. of the servo-power"and also to raise the as'zavss duced into the cylinder", but lsince thepiston is unsupported by the pawl anger 21, this pressure will operateto move the piston I2 outwardly; as indicated partially in dotted linesin Fi'g. 3 against the action of the spring Il, the dog 2l sliding underthe ilnger 21 in this operation. The switch 30 ,controls the applicationof hydraulic pressure to the casting material and in order for thecasting material to be injected into the dies, the switch plunger 3|must be depressed slightly. Failure to operate this switch renders thepressure injection of the casting material inoperative,

' thus accidental discharge or squirting of the finger 21 to allownormal .opening of the dies after the casting has been formed. as isindicated in Fig. 2.

The cycle of operation of the machine will be readily understood fromthe foregoing description when taken in connection with the diagrammaticillustrations in the drawing and the following statement. ConsideringFig. l, itwill be assumed that the dies Il have been moved into closedposition and the pawl 2| brought into theposition to engage the dog inthe recess 28 of the finger 21 of the pawl. At this time and through vsuitably controlled means oil or other pressure element is introducedinto the cylinders il through the tubes or pipes I5, .thus applying the"servo-power to the dies lli to firmly support the same in closedposition. In the same instant or very shortly thereafter in the cycle ofmachine operation, casting material is pressure injected into vthe diesat the parting line thereof through 'a gate or admission passage, notshown, in that it is disposed at right angles to the dies, to form acasting I4 in thecavities i1 and around a core pin 35. Immediatelythereafter the hydraulic or other pressure is released from thecylinders I4 and the dies are moved into open position as illustrated inFig. 2, the pawl 2| having been raised through operation of the rod 22,'as will be apparent. After removing the casting,

' .that the moment of application of the servopower in each cycle ofmachine operation represents in fact a small fractional part of eachcomplete cycle of machine operation and a fraction of a second. l

In Fig. 3 of the drawing is diagrammatically illustrated the fool-proofoperation of the machine, for example, in the event that the dies il!become improperly closed' by the presence of some foreign particle, asindicated atr in Fig. 3

l between adjacent surfaces of the dies Il. In

such instances the dog 20 will check downward movement of the pawl 2| orthe finger 21 thereof so that this finger will rest upon the uppersurface 31 of the dog, thus maintaining the finger 22 out of operativeengagement with the plunger 2| of the switch l0. The machine willperform its normal operation. In other words, the hydraulic or otherpressure medium will be introcasting material through the partiallyclosed dies i machines of this type and kind, suitable signal ordestruction 4to the dies is obviated.

It will lbe apparent that the pawl 2| operates in the mannerof a latch,which may be saidqto engage a bolt 2li, the dog extension on the piston,in checking outward movementof the piston and will be constructed insuch manner as to provide the required backing up of 'thepiston to carefor the application of the "servo-power" in closing and holding the diesclosed for the moment of pressure injection of the' casting material.

f `In the diagrammatic illustrations. all structural 'details withrespect to packings of Ithe pistons, etc. -have been omitted as theseare all well known in the arts. Furthermore, the invention is applicableto die casting machines of various types and kinds and in fact to anytype and kind of mechanisms where it is desirable to apply a finalpressure or stroke upon a moving part which has been otherwise movedinto a predetermined position. In accordance with the present teachings,the medium employed is introducedl b etween the moving part and whatmight be termed a backing member, automatically actuated means beingemployed controlling operative positionk of the backing member andotherwise controlling operation of the machine or apparatus.

Having fully described my invention, what I claim as new and desire tosecure by Letters a backing for each die and movable relatively to thedie. means` for injecting a pressure medium i said member in operativeposition.

asvavae a backing for each die and movable-relatively to the die, meansfor injecting a pressure ,medium between the die and said backing membertc move the die into closed position, means controlling the operativebacking up position of said member, said last named means comprising abolt on said member, a latch engaging the bolt to support said member inoperative position, and means preventing operative engagement of thelatch with said bolt in improper, mechanical, closing movement of thedie.

4. In die casting machines, a pair of dies movable toward and from eachother, mechanical means for actuating said dies, a member forming abacking for each die and movable relatively to the'die, means forinjecting a pressure medium between the die and said backing member tomove the die into closed position, means controlling the operativebacking up position of said member, said last named means comprising abolt on said member, a latch engaging the bolt to support said member inoperative position, means preventing operative .engagement of the latchwith said bolt in improper. mechanical, closing movement of the die, andsaid last named means including means preventing injection. of castingmaterial into improperly closed dies.

5. In a die casting machine, a pair of dies movable toward and from eachother, said dies having cylinder portions, pistons operating in the diecylinders, means comprising a latch adapted to operatively engage thepiston of each die cylinder, means for controlling normal mechanicalmovement of the dies toward and from each other, and means forintroducing a pressure medium between the dies and said pistonstosustain the dies in closed position, while said pistons are backed bysaid latch controlled means.

6. In a die casting machine, a pair of dies movable toward and from eachother, said dies having cylinder portions, pistons operating in the diecylinders, means comprising a latch adapted to operatively engage thepiston of each die cylinder, means for controlling 5normal mechanicalmovement of the dies toward and from each other, means for introducing apressure medium between the dies and said pistons to sustain the dies inclosed position, while said pistons are backed by said latch controlledmeans, and means providing yieliiable movement of the pistons relativelyto said dies.

7. In a die casting machine. a die, mechanical means for moving the dieinto open and closed positions, said die having an elongated cylinder, apiston in said cylinder and projecting outwardly through one end of thedie, means in the die for introducing a pressure medium into thecylinder at the other end of said piston to move the die into closedposition, means operatively engaging the rst named end of the piston toi'orm a back' ing maintaining the piston against movement in theaforesaid closing movement of said die, and means releasing said lastnamed means `in moving the die into open position.

8. In a die casting machine, a die, mechanical means for moving the dieinto open and closed positions, said die having an elongated cylinder,

a piston in said cylinder and projecting outwardly through one end ofthe die, means in the die for introducing a pressure medium into thecylinder at the other end of said piston to move the die into closedposition, means operatively engaging the first named end o! the pistonto :om s backing maintaining meetwaarden movement in the aforesaidclosing movement of said die, means releasing said last named means inmoving the die into open position, and said backing means comprising valatch engaging a projecting bolt on said piston.

9. In a die casting machine, a die, mechanical means for moving the dieinto open and closed positions, said die having an elongated cylinder, apiston in said cylinder and projecting outwardly through one end of thedie, means in the die for introducing a pressure medium into thecylinder at the other end o! said pistonv to move the die into closedposition, means operatively engaging the first named ond of the pistonto form a backing maintaining the piston against `movement in theaforesaid closing movement oi said die, means releasing said last namedmeans in moving the die into open position, said backing meanscomprising a latchv engaging a proiectins bolt on said piston, andspring means supporting` the piston in predetermined position in thecylinder of the die and providing relative movement between the die andpiston.

10. In a die casting machine employing mechanically actuated diesmovable toward and` from each other, in moving the dies into closed andopen positions, means for applying servopower to the dies in closing andholding the dies closed during pressure injection ot casting materialinto the dies, and means automatically relieving the servo-powerapplication in the event o! improper mechanical closure of `said dies.

11. In a die casting machine employing mechanically actuated diesmovable toward and from each other, in moving the dies` into closed andopen positions, means for applying servo-power to the dies in closingand holding the dies closed during pressure injection of castingmaterial into the dies, means automatically relieving the servopowerapplication in the event of improper mechanical closure of said dies,and said last named means including means e stoppingpressure injectionof casting material into improperly closed.

dies.

12. The combination with dies of a die casting machine, of a backingmember i'or the die,means cooperating with said member. retaining thesame in fixed backing-up position, means yieldably coupling the die withsaid member, and means for introducing a pressure medium between thebacking member and the die in applying servopower to the die insupporting the die in closed position.

13. In an apparatus of the class described, an element movable into openand closed positions, means for moving said element, said element havinga cylinder, a piston in said cylinder, yieldable means coupling thepiston and element providing movement therebetween, while normallymaintaining predetermined position of the piston in the cylinder of saidelement, a catch device automatically movable into and out of engagementwith said piston tov form a backing for said piston maintaining apredetermined position thereof, and means for introducing a pressuremedium into the cylinder of said element vto move the element relativelyto the piston, while the piston is maintained in backed position. 4

14. 'I'he combination with a die of a die casting machine having meansmechanically moving the die into open and closed position, of a backingmember movable with the die in normal opening and closing movementthereof, means automatically engaging said member tc support the same inbackIng-up position, and means iniecting a pressure medium between thebacked up member and the die to urge the die in a direction away fromsaid member in moving the die into closed position.

15. In a die casting machine employing dies movable toward and from eachother, mechanical means for actuating said dies, each die having acylinder and a backing member therein, andmeans for introducing `apressure medium into 10 16. In a die casting machine employing diesmovable toward and from each other. mechanical means for actuating saiddies, each die having a cylinder and a backing member therein, means forintroducing a pressure medium into said cylinders between said backingmembers and dies for applying holding pressure directly to the dies atthe moment of forming a casting within said dies, andmeans controllingthe last named operationof said dies. v 4

i LOUIS H. MOREL

